Dendritic cells exclusively mediate the cross-presentation of intravenous OVA in the spleen and intragastric OVA in the MLNs. Groups of mice were given 5 mg intravenous OVA or 100 mg intragastric OVA. Fourteen hours later, spleens or MLNs from the respective groups were obtained, and the low-density cells were isolated after collagenase digestion. Low-density cells were further sorted with anti-CD11c microbeads with or without prior depletion with anti-CD8α microbeads. CD11c^– cells were prepared from low-density cells after depletion of CD11c⁺ cells. Each population of cells was cocultured with CFSE-labeled OT-I T cells for 3 days and analyzed by flow cytometry. The percentages of cells that had divided are indicated. Data are representative of 5 experiments.